1. Field of the Invention
This invention relates to an apparatus for scraping solid materials from a conveyor surface, comprising a scraper blade element formed by a plurality of component blades which are aligned adjacent one another in a blade holder and which are supported to be applied against the conveyor surface to scrape solid material therefrom.
2. Statement of Prior Art
West German Published Application DE-OS 36 24 623 discloses an apparatus in which all of the component blades are applied to a conveyor belt surface under uniform pressure over the entire width of the blade element by a very elaborate construction. This construction includes a blade holder in which a separate mounting element is provided for each component blade of the blade element, consisting of an expandable pressure member supplied from a pressure-medium source, a flexible intermediate link connected thereto, a lever and a flexible blade fastening member. Although this known arrangement guarantees that, even if individual component blades wear, the component blades are automatically readjusted within certain limits without any need for manual intervention, this function is only achieved by means of the very elaborate blade mounting assembly which, in most cases, is unduly expensive and impractical because the apparatus must be connected to a supply of pressure medium during operation.
In addition, the very complicated structure of this known apparatus makes assembly and, in particular, the replacement of individual blades very complicated. Another particular disadvantage of this known apparatus is that the conveyor belt has to be stopped and, hence, production interrupted to replace a single component blade.
Another apparatus of the present type is disclosed in West German Patent Publication DE-OS 36 24 754. The apparatus of this publication also comprises a blade element having adjustable component blades, the blades being adjustable purely mechanically with no external supply of pressure medium. However, this known apparatus also has a very complicated structure which makes assembly and, particularly, the replacement of individual blades very difficult. Also, as with the other known apparatus discussed above, it is not possible to replace individual blades while the conveyor belt is in motion because an individual component blade can only be replaced after a support arm connected to a blade holder has been disconnected by complicated loosening of fastening bolts and corresponding lock nuts.